Fuse plug



June 28 J..C. TOURNIER FUSE PLUG Filed 'Ma 2, 1924 1 J 2% n .r i! O WW A 80 .5 2. H 1 m u J Patented June 28 1927.

UNITED STATES PATENT OFFICE- JULIUS C. TOURNIER, OF SCHENECTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

FUSE Application filed May 2,

The present invention relates to electric cut-outs and more especially to plug fuses of the magazine type.

The fuse plugs in commercial use are provided with a single fusible element or link and after one functioning are removed from their holders and scrapped, although all parts of the plugs other than the link are good as new. This practice has been long recognized as uneconomical and attempts have been made to provide fuse plugs with a. number of links whereby they may be rendered, capable of functioning at number of times, but so far as, known to me none of them, has gone into COITIIIIQIClfll use. This lack of practical utility is believed to be due to the fact that the reserve links of such prior magazineplugs have been connected, at least: at one end, to a normally live part of the plug, and upon the plug being blown under short circuit the reserve links have been fused along with the one actually in circuit and thereby nullifying the eX- pectcd :ulvantage of the magazine feature.

The object of my invention is the provision of an improved magazine fuse plug which shall. be adapted to receive and fully protect a number of reserve. links, which shall nn-mil; of ready and safe replacement of a. blown link and which may be manufactured at low cost.

One embodiment of my 'lllVQlltlOl'l is shown I in the accompanying drawing, in which Fig. 1 is a side elevation of the assembled plug; Fig. 2 is an axial section thereof; Fig. 3 is a perspective of the contact end of the plugand the central screw; Fig. 1 is a similar View of the barrier block; Fig. is ,a similar view of a single link and of a group of nested links adapted for use in my plug; and Fig. (i is a similar view of the handle or chambered part of the plug.

. The plug, as shown in the drawing, com prises three main parts of porcelain: the front or contact carrying member 1, the barrier bl. ck 2 and the chambered rear end or handle member 3. A center screw 4 extends axially through the main parts 1, 2 and 3, and serves to hold them clamped together in fixed relation.

The contact-carrying member 1 of the plug is made cup-shaped with a screw shell contact/5 enclosing the reduced endthereof and havin an inturned flange 6 connecting by a rivet T to a radial contact 8 carried on a PLUG.

1924. Serial No. 710,641.

ledge 9 within thecup-shaped portion. An insulating washer 10 is disposed outside the lange 6 and is caused to clamp the flange 6 to the end of the cup-shaped part 1 by means of an eyelet or hollow rivet 11 which passes therethrough and is spun over an end of a Z-shaped metal lead 12 to a second. radial contact 13 mounted on a ledge 1 1 opposite the ledge 9. V

" The barrier block 2 is shaped to substantially till the space between the ledges 9 and 14 of the cup-shaped part 1 and to project a sufficient distance outside thereof to provide anelfcctive barrier to any arcs that might otherwise tend to spring from one radial contact 8 to the other 13 or to 'the center screw 4.. The outer end of the block is provided with a notch 15, the purpose of which will be explained later.

The chambered rear end 3 of the plug is substantially cylindrical with longitudinal grooves 16 in. its outer surface to provide a hand hold, and its inner end has two raised 'adial ledges 17 and 18 adapted to enter the cup-shaped contact carrying part 1 and en gage against the radial contacts 8 and 13. Between the ledges 17 and 18, the plug part 3 is provided with two chambers 19 and 20' separated by a partition wall 21. One chamber serves as an explosion chamber and the other as a storage chamber. The outer end of the plug part 3 is provided with a recess in which is a nut 22 secured in place by cement 23 for engagement with the threaded end of the assembly screw 4.

The fuse links 24 are short sections of soft metal ribbon bent U shape with the ends turned outwardly to form contact feet 25, and at a point about half way between the ends is a small aperture 26 to definitely locate the weakest section thereof. The links are adapted to be bunched or nested, as indicated in Fig. 5, and one or two such bunches may be entered into one of the chambers 19 or 20 as a reserve supply, while a single link 24 will be located in the other chamber and with its contact feet held pressed into operative engagement with the radial contacts 8 and 13 by the ledges 17 and 18 hearing thereupon.

When a fuse link 24 has become blown. a fresh link will be taken from the reserve supply chamber and inserted in the explosion chamber formerly occupied by the blown link, the barrier block returned to place so that the partition wall 21 enters the notch 15 thereof. effectually to shut off one chamber from the other. One end of the block overlies and closes up the open end of the chamber with the reserve supply of links, while the other end of the block passes between the legs of the single link 2%, as indicated in Fig. 2, with their outturned feet 25 overlying the ledges l7 and 1.8. The contact carrying member 1 or the plug is placed in position over the barrier block and the screw 4 inserted and turned home, thereby causing the ledges 17 and 18 ot the rear member 3 to press the contact feet 25 ot the link into intimate engagement with the radial contacts 8 and 13. By reason ot the barrier block :2 entering between the ledges 9 and 14 ot' the contact-carrving part 1 and also between the ledges 17 and 18 of the rear part 3, the latter is positively p mented from swiveling relatively to the tormer part when torque is exerted thereon in screwing it into and out of its receptacle.

IVhile I have shown and described the best embodiment of the invention known to me, I do not desire to be restricted thereto.

hat I claim as new and desire to cure by Letters Patent of the United States 1s:

1. A fuse plug comprising a contact member provided with external contacts respectively connected to spaced internal contacts thereon, a handle member provided with means adapted to press the respective ends of a fuse link into engagement with said spaced internal contacts. and a central screw extending through one of said external contacts and engaging a thread in the handle member whereby said contact member and said handle member are clamped together.

2. A fuse plug comprising a contact niember provided with external contacts respectively connected to spaced internal contacts thereon, a handle member provided with spaced ledges adapted to press the respective ends of a fuse link into engagementwith said internal contacts, an arc resisting barrier member adapted to enter transversely between said spaced contacts of the contact member and said spaced ledges oi the handle member, and means for clamping said members together in fixed relation.

3. A fuse plug comprising a contact member, a handle member having an explosion chamber and a magazine chamber therein, and means for securing said contact member to the handle member over the open ends ot said chambers.

l. A fuse plug comprising a contact member having external contacts respectively connected to spaced internal contacts, a handle member having spaced ledges and two separate chambers between said ledges, and means for securing said members together and causing the said ledges to press the respective ends of a fuse link into ongagement with said internal contacts.

5. A fuse plug comprising a contact: member having external contacts respectively connected to spaced internal contacts. a handle member provided with spaced ledges corresponding to said spaced internal contacts, an explosion chamber and a magazine chamber in said handle member bet ween said spaced ledges. a barrier member entered between the said spaced internal contacts and between said spaced ledges to overlie and close said chambers, and securing means tor holding said members in fixed relation.

In witness whereof, I have hereunto set my hand this 1st day of May, 1924;.

JULIUS O. 'IOURNIER. 

